I know all the basic resizing stuff in AndEngine now but I haven't stumbled upon a good way on how to make text resizable. Basically what everybody is doing is that all fonts get declared as bitmaps with let's say 18pt and is hoping for the best. On the development device everything looks sharp and stuff but when switched onto a bigger device it looks quite ugly. Do I have to load all the Fonts into a bigger Atlas and then resize down? That can't be an option. Please help.
Is your question GLES2-specific? I don't think so.
The font size should not scale with the screen size but with the density. Maybe both. Anyway. In FluxCards I do this:
// determine the density
WindowManager windowManager = (WindowManager) getSystemService(WINDOW_SERVICE);
Display display = windowManager.getDefaultDisplay();
DisplayMetrics displayMetrics = new DisplayMetrics();
display.getMetrics(displayMetrics);
density = displayMetrics.density;
// scale desired size 25 by density
int fontSize = (int) (25 * density);
Texture fontTexture = new BitmapTextureAtlas(1024, 1024, TextureOptions.BILINEAR_PREMULTIPLYALPHA);
font = new Font(fontTexture, Typeface.create(Typeface.DEFAULT, Typeface.NORMAL), fontSize, true, Color.WHITE);
mEngine.getTextureManager().loadTexture(fontTexture);
mEngine.getFontManager().loadFont(font);
(My code is more complex and I still struggle with it as 1024x1024 is the maximum I can use for the fontTexture and with larger font and asian text, letters don't get written sometimes. I was searching for how to use Text in GLES2 and my 2 minutes reading before I ran into your question suggested that this is not an issue anymore.)